Flor Yeast Proteomics under a Biofilm and under a Non-Biofilm Forming Conditions: Biological Processes in which more abundant Proteins are involved

Abstract

In the Sherry wine elaboration process carried out in specific regions around the world, Saccharomyces cerevisiae “flor” yeast develops a velum (biofilm) on the wine surface. This velum remains along several years during the so called “biological aging” process and it contributes to the typical wine organoleptic properties. Besides biofilm formation, some others biological processes are regarded as essentials for the flor yeasts to survive. The aim of this work is to identify other biological processes apart from the biofilm formation which can be required for the flor yeast to survive in a biological aging condition. OFFGEL fractionator coupled to LTQ Orbitrap XL MS equipment were used trying to identify the maximum possible number of proteins in a biofilm forming condition (BFC) and under a reference non-biofilm forming condition (NBFC). Further, proteins were quantified and sorted by biological processes GO Terms by using the SGD database. Higher abundant proteins related with nucleus organization, cellular respiration, oligosaccharide metabolic process were found in the BFC. In the NBFC, proteins related with RNA splicing, ribosomal subunit export from nucleus and protein dephosphorylation were more abundant. Biological processes mentioned in this study may be essential for the flor yeast to survive in a BFC such as wines biologically aged. Genetic experiments are needed to definitively confirm the necessity of these proteins synthesis. All together may lead to the genetic improvement of flor yeast strains aimed to enhance their survival during the biological aging process and hence the whole Sherry wine elaboration process.